Diagnosing Alzheimer's: How Alzheimer's is diagnosed

To diagnose Alzheimer's disease, doctors conduct tests to assess memory impairment and other thinking skills, judge functional abilities, and identify behavior changes. They also perform a series of tests to rule out other possible causes of impairment.
By Mayo Clinic Staff

An accurate diagnosis of Alzheimer's disease is an important first step to ensure you have appropriate treatment, care, family education and plans for the future.

Early signs and symptoms of Alzheimer's

Early signs and symptoms of Alzheimer's disease include:

Memory impairment, such as difficulty remembering events

Difficulty concentrating, planning or problem-solving

Problems finishing daily tasks at home or at work

Confusion with location or passage of time

Having visual or space difficulties, such as not understanding distance in driving, getting lost or misplacing items

Language problems, such as word-finding problems or reduced vocabulary in speech or writing

Using poor judgment in decisions

Withdrawal from work events or social engagements

Changes in mood, such as depression or other behavior and personality changes

Alzheimer's disease can affect several aspects of your daily life.

When warning signs of Alzheimer's disease appear, it's important that you get a prompt and accurate diagnosis.

Diagnosing Alzheimer's

To diagnose Alzheimer's your primary doctor or a doctor trained in brain conditions (neurologist) will review your medical history, medication history and your symptoms. Your doctor will also conduct several tests.

During your appointment, your doctor will evaluate:

Whether you have impaired memory or thinking (cognitive) skills

Whether you exhibit changes in personality or behaviors

The degree of your memory or thinking impairment or changes

How your thinking problems affect your ability to function in daily life

The cause of your symptoms

Doctors may order additional laboratory tests, brain-imaging tests or send you for memory testing. These tests can provide doctors with useful information for diagnosis, including ruling out other diseases that cause similar symptoms.

Ruling out other diseases

Your doctor may order other tests to rule out diseases that may be causing your symptoms.

You may have laboratory tests to check for thyroid problems or vitamin B-12 deficiency.

You may be evaluated to determine if depression may be contributing to your symptoms.

Doctors will perform a physical evaluation and check that you don't have other health conditions that could be causing or contributing to your symptoms, such as signs of past strokes, Parkinson's disease or other medical conditions.

Neuropsychological tests. You may be evaluated by a specialist trained in brain conditions and mental health conditions (neuropsychologist). The evaluation can include extensive tests to evaluate your memory and thinking (cognitive) skills.

These tests help doctors determine if you have dementia, and if you're able to safely conduct daily tasks such as driving and managing your finances. They provide as much information on what you can still do as well as what you may have lost. These tests can also evaluate if depression may be causing your symptoms.

Interviews with friends and family. Doctors may ask your family member or friend questions about you and your behavior.

Doctors look for details that don't fit with your former level of function. Your family member or friend often can explain how your thinking (cognitive) skills, functional abilities and behaviors have changed over time.

This series of clinical assessments, the physical exam and the setting (age and duration of progressive symptoms) often provide doctors with enough information to make a diagnosis of Alzheimer's disease. However, when the diagnosis isn't clear, doctors may need to order additional tests.

Legal Conditions and Terms

Reprint Permissions

A single copy of these materials may be reprinted for noncommercial personal use only. "Mayo," "Mayo Clinic," "MayoClinic.org," "Mayo Clinic Healthy Living," and the triple-shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research.